Usurous vs. Usurious - What's the difference?

Usurious

Usury () is, as defined today, the practice of making unethical or immoral monetary loans that unfairly enrich the lender. Originally, usury meant interest of any kind. A loan may be considered usurious because of excessive or abusive interest rates or other factors. Historically, in some Christian societies, and in many Islamic societies even today, charging any interest at all would be considered usury. Someone who practices usury can be called a usurer, but a more common term in contemporary English is loan shark.
The term may be used in a moral sense—condemning, taking advantage of others' misfortunes—or in a legal sense where interest rates may be regulated by law. Historically, some cultures (e.g., Christianity in much of Medieval Europe, and Islam in many parts of the world today) have regarded charging any interest for loans as sinful.
Some of the earliest known condemnations of usury come from the Vedic texts of India. Similar condemnations are found in religious texts from Buddhism, Judaism, Christianity, and Islam (the term is riba in Arabic and ribbit in Hebrew). At times, many nations from ancient Greece to ancient Rome have outlawed loans with any interest. Though the Roman Empire eventually allowed loans with carefully restricted interest rates, the Catholic Church in medieval Europe banned the charging of interest at any rate (as well as charging a fee for the use of money, such as at a bureau de change).